1. Technical Field
The present invention relates to a sub sea processing system in connection with the production of oil and/or gas from one or more wells, especially wells producing heavy oil in deep water and with high viscosity.
2. Description of the Related Art
Oil and gas sub-sea field developments in deeper waters and closer to arctic areas face various technical challenges as a result of the more hostile environmental conditions. Overcoming these challenges requires a combination of careful and innovative design of production systems, and extensive and tightly controlled multi-phase flow assurance, as well as operational strategies and procedures. Design of sub-sea production systems normally begins with fluid characterization followed by establishment of a field architecture and development of economical flow-line configurations consistent with safety and minimum intervention requirements. Understanding and designing for the various flow assurance conditions and requirements of the deep water system may lead to minimum intervention and the least possible production loss. The performance goal for steady state operations should be to achieve platform arrival temperatures above hydrate formation temperatures and/or wax appearance temperature (WAT) as a minimum. The performance goal for transient, i.e. shut-in, operations is to achieve adequate, cool-down time before the pipe contents cool to the hydrate formation temperature after shut-in. Besides shut-in, depressurization and wax removal come into play as other major transient challenges in deeper waters.
Sub-sea pipeline bundles are commonly known and represent enhanced pipeline systems for the transportation of oil and gas and remote operation of sub-sea oil and gas wells. Such bundles may include a carrier pipe (outer casing or shell), within which may be provided one or more flow-lines for oil and gas, pipeline(s) or other arrangement for heating as well as hydraulic and/or electric control lines for the remote operation of the wells. This bundle solution may provide highly efficient thermal insulation and/or active heating elements to minimize thermal losses.
Bundle solutions are commonly used, among other situations, where the operation takes place in deep water, where seabed areas are congested, where diverless operations are mandatory or where anchor patterns restrict available seabed. However, bundle solutions as such do not solve the challenges associated with well operations in deep water with low temperature and production of heavy oil with high viscosity, but may be included in the solutions designed for such situations.